The House of Commons passed the bill a week ago and its failure in a Senate committee doesn’t mean it’s dead, but the vote is a blow for Prime Minister Justin Trudeau and the Liberals.

Bill C-48 would put into a law a longstanding voluntary moratorium on coastal tanker traffic between the northern tip of Vancouver Island and the Alaska border, which is meant to protect delicate marine environments from potential spills.

More precisely, the bill would forbid tankers carrying more than 12,500 tonnes of oil from loading or unloading in the exclusion zone, either directly at ports or by using other ships as intermediaries.

Simons said late in the debate that she wasn’t confident that enough homework had been done to justify a permanent ban — that the bill would lock in a temporary measure based on limited research more than 40 years ago.

“I felt it was important as an Albertan, as a member on this committee, to come here with goodwill, to work towards amendments that would somehow strike a compromise where we could both protect one of Canada’s most extraordinary ecosystems while simultaneously not slamming the door in the face of the people of Alberta,” Simons said.

She might have backed a temporary legal restriction on tankers to allow further research, she said, but couldn’t support the bill as it stood.

Along with Bill C-69, which is meant to reform the federal assessment process for national-scale construction projects and is also in the Senate, Bill C-48 has enraged many backers of the Canadian oil industry, including Alberta Premier Jason Kenney.

“This is a victory for common sense & economic growth,” Kenney tweeted after the vote. “Thank-you to Senators for listening to Albertans & respecting fairness in our federation!”

Conservatives in the Senate said voting down the bill is a win for Canada’s energy industry, leaving open the possibility of exporting Canadian oil from northern B.C. ports.

The now-aborted Northern Gateway pipeline project, for instance, would have carried Alberta oil to Kitimat, B.C., in the no-tanker zone.

“This bill would only make the issue of landlocked Canadian oil worse,” said a statement from Sen. Larry Smith, the Conservative leader in the Senate.

The statement pointed out that Bill C-48 would forbid the transfer of oil onto or off ships in northern B.C. but wouldn’t stop tankers from passing through the area, impeding Canadian oil but not outlawing tanker traffic from Alaska.

The bill has divided First Nations. Some, such as the Nisga’a, see economic opportunity in pipelines. Others, including a nine-nation alliance of coastal First Nations, worry about irreversible damage to fisheries and nascent industries based on products such as essential oils from old-growth trees.